Bobby Heck has experienced this before. The whole rebuilding thing can be a thankless task and you're not always there to reap the benefits, but the Astros' assistant general manager of scouting knows exactly how to operate in this setting.

He did it when he was with the Brewers, working as part of a scouting staff that brought in some game-changing talent via the First-Year Player Draft. Heck was gone, off to become Houston's scouting director, by the time Milwaukee had completed the rebuilding and made the playoffs, but he saw from afar the fruits of his and his colleagues' labor. And he knows it doesn't come overnight.

"The patience part of it, I've been there before," Heck said, sitting in the stands between games of the East Coast Pro Showcase in Syracuse, where he was trying to get a read of potential new talent for the 2013 Draft. "It takes the efforts of many to rebuild a Minor League system. I was surrounded by good baseball people in Milwaukee, and I'm surrounded by a very good team in Houston. You learn patience going through a long-term rebuild, the pain of it and the time element of it.

"I missed the meaningful games of September and October that the Brewers eventually played after I departed for this opportunity with Houston, but I really look forward to when our competing window opens."

When that window opens remains to be seen, but there is no question the Astros' farm system will help crack it much sooner than people may have thought a few years ago. A once-barren system has been restocked, largely via acquisitions over the past two Trade Deadline periods, and also via the Draft.

A look at the current list of Houston's Top 20 prospects provides an ideal snapshot of just how much things have changed. A total of 12 of the 20 players came from Trade Deadline deals in 2011 and 2012. No. 5, shortstop Jonathan Villar, came in a 2010 Deadline trade; No. 20, right-hander Kyle Weiland, came during the offseason; and No. 18, left-hander Kevin Chapman, joined the organization in March. While Houston may not have been able to land the big-name elite prospects, they added both quality and quantity in those deals.

"There are 30 clubs that can view players differently," Heck said. "We have a very capable professional [scouting] staff. Our amateur staff gets involved to a degree. We have a very strong analytical department led by Sig Mejdal that we didn't have in prior years. They're very much involved in both our amateur and professional evaluations and acquisition of talent. We're very confident in our processes."

Things have changed so much that even when players are acquired, it is no longer an automatic that they are added to that Top 20. Case in point: outfielder Bobby Borchering, who came from the D-backs in the Chris Johnson deal. A year or two ago, Borchering may have even been a Top 10 prospect in the Astros system. Now, he's on the outside looking in. That's no slight to Borchering, but it does speak volumes about the strength of the farm these days.

"It was no secret that we were No. 30 in terms of our farm system," Heck said. "Now I think we've built it into a top-10 system."

Winning percentage isn't the be-all, end-all in development, but the stark contrast between this year and seasons past is another indication things are moving in an encouraging direction. In 2010, the Astros' affiliates combined to finish 29th in baseball with a .435 winning percentage. They were in the cellar, at .408, the following year. Not a single affiliate finished over .500 in 2011. This year? Houston's farm system sits in second place with a .539 winning percentage. All but its Gulf Coast League and Dominican Summer League teams are currently over .500.

"I think within the industry, people have recognized the progress we've made," Heck said. "A lot of our guys are putting quality seasons together and getting noticed outside of our organization. We had the worst winning percentage in the Minor Leagues the last two years, this year we've been near the top all season. That's a testament to the patience that's required with younger players, the work [director of player development] Fred Nelson and our player-development staff has done with those we've continued to add through the Draft, the trades from the last two years and internationally."

As much as the trading of Major League talent has replenished their system, the Astros have also done a good job of adding in the other ways Heck mentioned. And they haven't always gone the safe route. With the team struggling at the Major League level, there was surely pressure to draft college players who would get to Houston quickly and make contributions sooner. But that's not the direction Heck and the scouting staff headed in.

"We weren't just looking for the safest or surest returns [in the Draft], we were looking for pillars," Heck said. "We didn't just want players, we wanted impact players. Did that mean we took on more risk? Absolutely. But it's something we had to do.

"A lot of times, we've taken players that weren't who people thought we'd take or should take, like Delino DeShields, even Carlos Correa this year. Some picks haven't been consensus, but most of them are now outperforming and producing."

The added depth will allow the Astros to take their time with some of those players. DeShields, a second baseman and son of the former Major Leaguer of the same name, was pushed to the South Atlantic League in 2011 and struggled. Now, with more talent above and around him, Houston could afford to send DeShields back to Lexington, where he's flourished. He is still only 19.

Then there was the 2012 Draft. No one used the new system better than the Astros did. Granted, picking No. 1 overall helps, but they were highly creative in using their Draft pool money to sign not just Correa, the shortstop from Puerto Rico who was the No. 1 overall pick, but other high-end players in pitcher Lance McCullers and third baseman Rio Ruiz.

"A lot of the credit goes to general manager, Jeff Luhnow, our owner, Jim Crane, and our team president, George Postolos," Heck said. "Our approach was, 'How do we get the most first-round talent?' It was putting the pool of money we were allotted with and trying to score the best return. Frankly, we feel we got three top-15 picks with Correa, McCullers and Ruiz. We felt we needed multiples of potential impact players in our current state."

The current state in Houston is one of need. The influx of talent hasn't arrived yet and if the season were to end today, the Astros would get the No. 1 overall pick again next year. But Heck knows as well as anyone that patience is a virtue in a rebuilding process and that there is a light at the end of the proverbial tunnel.

"The players will determine the time element," Heck said. "You can have a great baseball business plan, but the players can step up and accelerate it, a la Oakland this season. There's a team every year you can point to that thinks they're two years away and then they compete. We'll keep an eye on how our guys do."

Jonathan Mayo is a reporter for MLB.com and writes a blog, B3. Follow @JonathanMayoB3 on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.